1. Field of the Invention
The present invention relates to a three-dimensional (3D) magnetic sensor chip, especially to a sensor chip which can measure the magnetic flux magnitude in 3D on a plane using a magnetic flux bending concentrating structure.
2. The Prior Arts
Magnetic sensors have been widely used in various fields, and are mainly used to detect magnetic fields. For example, magnetic sensors are used in the magnetic sensors of the earth, linear sensors, and angular sensors and switch sensors to detect the magnetic field so as to perform direction positioning, navigation or measurement. As the technology advances, such as the vehicle navigation systems and smart phones, the need of magnetic sensors in the navigation field has also grown. With the characteristics of magnetic sensing, magnetic sensors can be quickly applied in the navigation and global positioning system. It is the trend of modern electronic design to combine devices with different function into a single electronic product, thus, as the size of the product grows smaller, the design of the magnetic sensors is also challenged.
A conventional magnetic sensor unit includes three magnetic sensing devices of the same structure, where the two magnetic sensing devices are disposed in the vertical direction of a plane to measure the magnitude of the magnetic flux in the X and Y axes. The other magnetic sensing device, which is used to measure the Z axis magnitude of the magnetic flux, is disposed vertically to the other two magnetic sensing devices. As the design of the integrated circuits grows smaller, the vertical connection between the magnetic sensing devices has to be done in two-stages. In addition, the vertical connection is hard to be standardized, thus the yield is low, failure is more likely to happen and the overall production cost is increased.
Therefore, manufacturers thereof are in an urgent to develop a sensor structure with a smaller size, in which the magnetic sensing devices of three directions thereof are placed on the same plane, to resolve the manufacturing problems mentioned above.